When Kim Jong Un took the helm of North Korea in late 2011, speculation swirled around the young, Swiss-educated leader. What would he do for an economically backward authoritarian nation that had been in a high-stakes nuclear standoff with its neighbors and Washington for years?

Almost six years later, there are still unanswered questions, but some things about Kim have come into focus. His rule has actually seen the economy improve, and when it comes to the nuclear drive, it's obvious that Kim, who rattled nerves last week by test-firing his country's first intercontinental ballistic missile, has a more uncompromising stance than his late father, Kim Jong Il, who occasionally sat down for talks with Washington meant to gain concessions.

Kim Jong Un seems uninterested in negotiations until he perfects a nuclear missile capable of striking anywhere in the United States.

The stance has so far worked, and he'll likely achieve the badly needed nuclear deterrence against the United States fairly soon if he's not stopped.

Here's a look at Kim's nuclear gamble and what the future might hold.

WHAT HE'S DOING

His father, who ruled North Korea from 1994 to 2011, also ordered a string of weapons tests, but he let diplomats pursue now-dormant international disarmament-for-aid deals.

No such talks have happened under Kim Jong Un. He has overseen three of the North's five atomic test explosions and both of its successful satellite launches, which are seen by the U.N. as a disguised test of long-range missile technology.

And then there's the July 4 ICBM launch, the North's most successful missile test to date. Afterward, Kim said he will never put his nuclear and missile programs on the negotiating table as long as U.S. hostility and nuclear threats persist.

What accounts for Kim's boldness?

It might just be his nature. Kim, believed to be around 33, may have strategically chosen to push the nuclear program after determining that the United States won't attack because of fears that a North Korean retaliation would cause enormous casualties in South Korea.

Kim may also have determined that China, North Korea's main ally and aid benefactor, might agree to tougher international sanctions against North Korea but would stop short of doing anything to bring down Kim's government, which could trigger a flood of refugees over their shared border and potentially a unified Korea with U.S.-allied Seoul in charge.

North Korea's small yet gradual economic growth in recent years has also allowed Kim to focus on furthering his nuclear ambitions. His father, by comparison, resorted to outside handouts to feed many of his 24 million people after a devastating famine in the mid-1990s killed tens of thousands.

WHAT HE WANTS

Kim's propaganda machine argues that the nuclear deterrence is a "treasured sword" meant to cope with U.S. aggression.

"Kim doesn't want to resolve issues through diplomacy. He's just trying to protect himself by reinforcing his country's military power," said analyst Cheong Seong-Chang at South Korea's Sejong Institute.

Since his inauguration, Kim has not met any foreign leaders or traveled abroad. The most high-profile foreigner he has met: former NBA star Dennis Rodman, who regaled him with a rendition of "Happy Birthday" at an exhibition game during one of several trips to Pyongyang.

Kim has repeatedly promised to achieve Korean unification, and he likely thinks his nuclear bombs will deter U.S. involvement in the event of another war on the Korean Peninsula. "If North Korea demonstrates its ability to strike Washington and New York ... and threatens to turn them into a sea of fire, the U.S. couldn't easily enter a war," Cheong said.

After perfecting a functioning ICBM, which could take a couple of years, Kim could push for talks to win big outside concessions in return for imposing a moratorium on nuclear and missile activities. Even so, he won't likely give up his already-developed weapons.

In the event of such talks, Kim would likely want big aid packages, the suspension of annual U.S.-South Korean military drills that North Korea views as an invasion rehearsal, and the signing of a peace treaty officially ending the 1950-53 Korean War, which would allow him to push for the withdrawal of the 28,500 American troops stationed in South Korea.

WHAT STANDS IN HIS WAY

Kim's dogged quest for nuclear weapons may also relate to his hunger to be seen by his people as a strong leader and to establish the same absolute power held by his father and his grandfather, national founder Kim Il Sung.

This would make it hard for him to back off.

"He cannot give up nukes because they are the core of his power," said Cho Han Bum, an analyst at South Korea's Korea Institute for National Unification.

The North Korean ICBM could be capable of reaching Alaska, but weapons experts say the North still needs to master several more technologies before the missile will work perfectly.

When that happens, the United States might reconsider military strikes so as not to let other rogue states think they could get their own nuclear programs if they simply hold out, Cho said.

Aside from a U.S. attack, the most painful measure against North Korea could be a Chinese suspension or drastic scaling back of its oil shipments to the North.

China sends about 500,000 tons of crude oil to North Korea, mostly for free, every year. That accounts for 80-90 percent of the North's domestic consumption, according to Cho Bong-hyun of Seoul's IBK Economic Research Institute.

It's not clear if China would suspend the shipments even if North Korea's nuclear threat becomes more dangerous. But if a suspension happened, the North's military, the backbone of Kim's rule, would suffer because it cannot effectively fly warplanes and operate tanks without oil.

That will lead to Kim's grip on power loosening, Cheong predicts.

"We can see he's so far run North Korea in a smarter way than his father because the economic conditions have improved and the military power has been bolstered," Cheong said. "But there is a high possibility that his adventurous, uncompromising attitude will eventually make things turn out badly."

Ruthless dictator? Economic reformer? Shrewd master of nuclear brinksmanship?When Kim Jong Un took the helm of North Korea in late 2011, speculation swirled around the young, Swiss-educated leader. What would he do for an economically backward authoritarian nation that had...